December 2024 - Linux-kselftest-mirror

[PATCH RFC v3 00/10] extensible syscalls: CHECK_FIELDS to allow for easier feature detection

by Aleksa Sarai

This is something that I've been thinking about for a while. We had a discussion at LPC 2020 about this[1] but the proposals suggested there never materialised. In short, it is quite difficult for userspace to detect the feature capability of syscalls at runtime. This is something a lot of programs want to do, but they are forced to create elaborate scenarios to try to figure out if a feature is supported without causing damage to the system. For the vast majority of cases, each individual feature also needs to be tested individually (because syscall results are all-or-nothing), so testing even a single syscall's feature set can easily inflate the startup time of programs. This patchset implements the fairly minimal design I proposed in this talk[2] and in some old LKML threads (though I can't find the exact references ATM). The general flow looks like: 1. Userspace will indicate to the kernel that a syscall should a be no-op by setting the top bit of the extensible struct size argument. We will almost certainly never support exabyte sized structs, so the top bits are free for us to use as makeshift flag bits. This is preferable to using the per-syscall flag field inside the structure because seccomp can easily detect the bit in the flag and allow the probe or forcefully return -EEXTSYS_NOOP. 2. The kernel will then fill the provided structure with every valid bit pattern that the current kernel understands. For flags or other bitflag-like fields, this is the set of valid flags or bits. For pointer fields or fields that take an arbitrary value, the field has every bit set (0xFF... to fill the field) to indicate that any value is valid in the field. 3. The syscall then returns -EEXTSYS_NOOP which is an errno that will only ever be used for this purpose (so userspace can be sure that the request succeeded). On older kernels, the syscall will return a different error (usually -E2BIG or -EFAULT) and userspace can do their old-fashioned checks. 4. Userspace can then check which flags and fields are supported by looking at the fields in the returned structure. Flags are checked by doing an AND with the flags field, and field support can checked by comparing to 0. In principle you could just AND the entire structure if you wanted to do this check generically without caring about the structure contents (this is what libraries might consider doing). Userspace can even find out the internal kernel structure size by passing a PAGE_SIZE buffer and seeing how many bytes are non-zero. As with copy_struct_from_user(), this is designed to be forward- and backwards- compatible. This allows programas to get a one-shot understanding of what features a syscall supports without having to do any elaborate setups or tricks to detect support for destructive features. Flags can simply be ANDed to check if they are in the supported set, and fields can just be checked to see if they are non-zero. This patchset is IMHO the simplest way we can add the ability to introspect the feature set of extensible struct (copy_struct_from_user) syscalls. It doesn't preclude the chance of a more generic mechanism being added later. The intended way of using this interface to get feature information looks something like the following (imagine that openat2 has gained a new field and a new flag in the future): static bool openat2_no_automount_supported; static bool openat2_cwd_fd_supported; int check_openat2_support(void) { int err; struct open_how how = {}; err = openat2(AT_FDCWD, ".", &how, CHECK_FIELDS | sizeof(how)); assert(err < 0); switch (errno) { case EFAULT: case E2BIG: /* Old kernel... */ check_support_the_old_way(); break; case EEXTSYS_NOOP: openat2_no_automount_supported = (how.flags & RESOLVE_NO_AUTOMOUNT); openat2_cwd_fd_supported = (how.cwd_fd != 0); break; } } This series adds CHECK_FIELDS support for the following extensible struct syscalls, as they are quite likely to grow flags in the near future: * openat2 * clone3 * mount_setattr [1]: https://lwn.net/Articles/830666/ [2]: https://youtu.be/ggD-eb3yPVs Signed-off-by: Aleksa Sarai <cyphar(a)cyphar.com> --- Changes in v3: - Fix copy_struct_to_user() return values in case of clear_user() failure. - v2: <https://lore.kernel.org/r/20240906-extensible-structs-check_fields-v2-0-0f4…> Changes in v2: - Add CHECK_FIELDS support to mount_setattr(2). - Fix build failure on architectures with custom errno values. - Rework selftests to use the tools/ uAPI headers rather than custom defining EEXTSYS_NOOP. - Make sure we return -EINVAL and -E2BIG for invalid sizes even if CHECK_FIELDS is set, and add some tests for that. - v1: <https://lore.kernel.org/r/20240902-extensible-structs-check_fields-v1-0-545…> --- Aleksa Sarai (10): uaccess: add copy_struct_to_user helper sched_getattr: port to copy_struct_to_user openat2: explicitly return -E2BIG for (usize > PAGE_SIZE) openat2: add CHECK_FIELDS flag to usize argument selftests: openat2: add 0xFF poisoned data after misaligned struct selftests: openat2: add CHECK_FIELDS selftests clone3: add CHECK_FIELDS flag to usize argument selftests: clone3: add CHECK_FIELDS selftests mount_setattr: add CHECK_FIELDS flag to usize argument selftests: mount_setattr: add CHECK_FIELDS selftest arch/alpha/include/uapi/asm/errno.h | 3 + arch/mips/include/uapi/asm/errno.h | 3 + arch/parisc/include/uapi/asm/errno.h | 3 + arch/sparc/include/uapi/asm/errno.h | 3 + fs/namespace.c | 17 ++ fs/open.c | 18 ++ include/linux/uaccess.h | 97 ++++++++ include/uapi/asm-generic/errno.h | 3 + include/uapi/linux/openat2.h | 2 + kernel/fork.c | 30 ++- kernel/sched/syscalls.c | 42 +--- tools/arch/alpha/include/uapi/asm/errno.h | 3 + tools/arch/mips/include/uapi/asm/errno.h | 3 + tools/arch/parisc/include/uapi/asm/errno.h | 3 + tools/arch/sparc/include/uapi/asm/errno.h | 3 + tools/include/uapi/asm-generic/errno.h | 3 + tools/include/uapi/asm-generic/posix_types.h | 101 ++++++++ tools/testing/selftests/clone3/.gitignore | 1 + tools/testing/selftests/clone3/Makefile | 4 +- .../testing/selftests/clone3/clone3_check_fields.c | 264 +++++++++++++++++++++ tools/testing/selftests/mount_setattr/Makefile | 2 +- .../selftests/mount_setattr/mount_setattr_test.c | 53 ++++- tools/testing/selftests/openat2/Makefile | 2 + tools/testing/selftests/openat2/openat2_test.c | 165 ++++++++++++- 24 files changed, 777 insertions(+), 51 deletions(-) --- base-commit: 98f7e32f20d28ec452afb208f9cffc08448a2652 change-id: 20240803-extensible-structs-check_fields-a47e94cef691 Best regards, -- Aleksa Sarai <cyphar(a)cyphar.com>

8 months, 3 weeks

6
21
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[PATCH 0/1] selftests: Clear -Wimplicit-function-declaration warnings

by Ariel Otilibili

Hello, This patch clears out warnings seen while compiling the tests; at the time, it closes a test report. Thank you, Link: https://lore.kernel.org/oe-kbuild-all/202412222015.lMBH62zB-lkp@intel.com/ Ariel Otilibili (1): selftests: Clear -Wimplicit-function-declaration warnings tools/testing/selftests/pid_namespace/pid_max.c | 1 + tools/testing/selftests/pidfd/pidfd_fdinfo_test.c | 1 + 2 files changed, 2 insertions(+) -- 2.43.0

8 months, 3 weeks

2
2
0 0

[PATCH 0/3] Fix test_bpf_syscall_macro selftest on powerpc

by Saket Kumar Bhaskar

Since, syscall wrapper is supported on powerpc with syscall entry symbols as sys_*, changes done to fix selftests like test_bpf_syscall_macro, attach_probe/auto, etc. Saket Kumar Bhaskar (3): libbpf: Fix accessing the syscall argument on powerpc libbpf: Remove powerpc prefix from syscall function names selftests/bpf: Define SYS_PREFIX for powerpc tools/lib/bpf/bpf_tracing.h | 9 +++++++-- tools/lib/bpf/libbpf.c | 10 ++++++++-- tools/testing/selftests/bpf/progs/bpf_misc.h | 3 +++ 3 files changed, 18 insertions(+), 4 deletions(-) -- 2.43.5

9 months

2
12
0 0

[PATCH v4 0/3] Migrate PCI Endpoint Subsystem tests to Kselftest

by Manivannan Sadhasivam

Hi, This series carries forward the effort to add Kselftest for PCI Endpoint Subsystem started by Aman Gupta [1] a while ago. I reworked the initial version based on another patch that fixes the return values of IOCTLs in pci_endpoint_test driver and did many cleanups. Since the resulting work modified the initial version substantially, I took over the authorship. This series also incorporates the review comment by Shuah Khan [2] to move the existing tests from 'tools/pci' to 'tools/testing/kselftest/pci_endpoint' before migrating to Kselftest framework. I made sure that the tests are executable in each commit and updated documentation accordingly. - Mani [1] https://lore.kernel.org/linux-pci/20221007053934.5188-1-aman1.gupta@samsung… [2] https://lore.kernel.org/linux-pci/b2a5db97-dc59-33ab-71cd-f591e0b1b34d@linu… Changes in v4: * Dropped the BAR fix patches and submitted them separately: https://lore.kernel.org/linux-pci/20241231130224.38206-1-manivannan.sadhasi… * Rebased on top of pci/next 9e1b45d7a5bc0ad20f6b5267992da422884b916e Changes in v3: * Collected tags. * Added a note about failing testcase 10 and command to skip it in documentation. * Removed Aman Gupta and Padmanabhan Rajanbabu from CC as their addresses are bouncing. Changes in v2: * Added a patch that fixes return values of IOCTL in pci_endpoint_test driver * Moved the existing tests to new location before migrating * Added a fix for BARs on Qcom devices * Updated documentation and also added fixture variants for memcpy & DMA modes Manivannan Sadhasivam (3): misc: pci_endpoint_test: Fix the return value of IOCTL selftests: Move PCI Endpoint tests from tools/pci to Kselftests selftests: pci_endpoint: Migrate to Kselftest framework Documentation/PCI/endpoint/pci-test-howto.rst | 155 ++++------ MAINTAINERS | 2 +- drivers/misc/pci_endpoint_test.c | 250 ++++++++--------- tools/pci/Build | 1 - tools/pci/Makefile | 58 ---- tools/pci/pcitest.c | 264 ------------------ tools/pci/pcitest.sh | 73 ----- tools/testing/selftests/Makefile | 1 + .../testing/selftests/pci_endpoint/.gitignore | 2 + tools/testing/selftests/pci_endpoint/Makefile | 7 + tools/testing/selftests/pci_endpoint/config | 4 + .../pci_endpoint/pci_endpoint_test.c | 194 +++++++++++++ 12 files changed, 386 insertions(+), 625 deletions(-) delete mode 100644 tools/pci/Build delete mode 100644 tools/pci/Makefile delete mode 100644 tools/pci/pcitest.c delete mode 100644 tools/pci/pcitest.sh create mode 100644 tools/testing/selftests/pci_endpoint/.gitignore create mode 100644 tools/testing/selftests/pci_endpoint/Makefile create mode 100644 tools/testing/selftests/pci_endpoint/config create mode 100644 tools/testing/selftests/pci_endpoint/pci_endpoint_test.c -- 2.25.1

9 months

2
14
0 0

[PATCH v8 0/2] selftests/resctrl: SNC kernel support discovery

by Maciej Wieczor-Retman

Changes v8: - Fix Makefile changes. - Update cover letter SNC status information. - Add Reinette's reviewed by tag to patch 2/2. Changes v7: - Include fallthrough in resctrlfs.c. - Check fp after opening empty cpus file. - Correct a comment and merge strings in snprintf(). Changes v6: - Rebase onto latest kselftest-next. - Looking at the two patches with a fresh eye decided to make a split along the lines of: - Patch 1/2 contains all of the code that relates to SNC mode detection and checking that detection's reliability. - Patch 2/2 contains checking kernel support for SNC and modifying the messages at the end of affected tests. Changes v5: - Tests are skipped if snc_unreliable was set. - Moved resctrlfs.c changes from patch 2/2 to 1/2. - Removed CAT changes since it's not impacted by SNC in the selftest. - Updated various comments. - Fixed a bunch of minor issues pointed out in the review. Changes v4: - Printing SNC warnings at the start of every test. - Printing SNC warnings at the end of every relevant test. - Remove global snc_mode variable, consolidate snc detection functions into one. - Correct minor mistakes. Changes v3: - Reworked patch 2. - Changed minor things in patch 1 like function name and made corrections to the patch message. Changes v2: - Removed patches 2 and 3 since now this part will be supported by the kernel. Sub-Numa Clustering (SNC) allows splitting CPU cores, caches and memory into multiple NUMA nodes. When enabled, NUMA-aware applications can achieve better performance on bigger server platforms. SNC support was merged into the kernel [1]. With SNC enabled and kernel support in place all the tests will function normally (aside from effective cache size). There might be a problem when SNC is enabled but the system is still using an older kernel version without SNC support. Currently the only message displayed in that situation is a guess that SNC might be enabled and is causing issues. That message also is displayed whenever the test fails on an Intel platform. Add a mechanism to discover kernel support for SNC which will add more meaning and certainty to the error message. Add runtime SNC mode detection and verify how reliable that information is. Series was tested on Ice Lake server platforms with SNC disabled, SNC-2 and SNC-4. The tests were also ran with and without kernel support for SNC. Series applies cleanly on kselftest/next. [1] https://lore.kernel.org/all/20240716065458.GAZpYZQhh0PBItpD1k@fat_crate.loc… Previous versions of this series: [v1] https://lore.kernel.org/all/cover.1709721159.git.maciej.wieczor-retman@inte… [v2] https://lore.kernel.org/all/cover.1715769576.git.maciej.wieczor-retman@inte… [v3] https://lore.kernel.org/all/cover.1719842207.git.maciej.wieczor-retman@inte… [v4] https://lore.kernel.org/all/cover.1720774981.git.maciej.wieczor-retman@inte… [v5] https://lore.kernel.org/all/cover.1730206468.git.maciej.wieczor-retman@inte… [v6] https://lore.kernel.org/all/cover.1733136454.git.maciej.wieczor-retman@inte… [v7] https://lore.kernel.org/all/cover.1733741950.git.maciej.wieczor-retman@inte… Maciej Wieczor-Retman (2): selftests/resctrl: Adjust effective L3 cache size with SNC enabled selftests/resctrl: Discover SNC kernel support and adjust messages tools/testing/selftests/resctrl/Makefile | 1 + tools/testing/selftests/resctrl/cmt_test.c | 4 +- tools/testing/selftests/resctrl/mba_test.c | 2 + tools/testing/selftests/resctrl/mbm_test.c | 4 +- tools/testing/selftests/resctrl/resctrl.h | 6 + .../testing/selftests/resctrl/resctrl_tests.c | 9 +- tools/testing/selftests/resctrl/resctrlfs.c | 137 ++++++++++++++++++ 7 files changed, 158 insertions(+), 5 deletions(-) -- 2.47.1

9 months

3
9
0 0

[PATCH v2] kunit: Introduce autorun option

by Stanislav Kinsburskii

The new option controls tests run on boot or module load. With the new debugfs "run" dentry allowing to run tests on demand, an ability to disable automatic tests run becomes a useful option in case of intrusive tests. The option is set to true by default to preserve the existent behavior. It can be overridden by either the corresponding module option or by the corresponding config build option. Signed-off-by: Stanislav Kinsburskii <skinsburskii(a)linux.microsoft.com> --- include/kunit/test.h | 4 +++- lib/kunit/Kconfig | 12 ++++++++++++ lib/kunit/debugfs.c | 2 +- lib/kunit/executor.c | 21 +++++++++++++++++++-- lib/kunit/test.c | 6 ++++-- 5 files changed, 39 insertions(+), 6 deletions(-) diff --git a/include/kunit/test.h b/include/kunit/test.h index 34b71e42fb10..58dbab60f853 100644 --- a/include/kunit/test.h +++ b/include/kunit/test.h @@ -312,6 +312,7 @@ static inline void kunit_set_failure(struct kunit *test) } bool kunit_enabled(void); +bool kunit_autorun(void); const char *kunit_action(void); const char *kunit_filter_glob(void); char *kunit_filter(void); @@ -334,7 +335,8 @@ kunit_filter_suites(const struct kunit_suite_set *suite_set, int *err); void kunit_free_suite_set(struct kunit_suite_set suite_set); -int __kunit_test_suites_init(struct kunit_suite * const * const suites, int num_suites); +int __kunit_test_suites_init(struct kunit_suite * const * const suites, int num_suites, + bool run_tests); void __kunit_test_suites_exit(struct kunit_suite **suites, int num_suites); diff --git a/lib/kunit/Kconfig b/lib/kunit/Kconfig index 34d7242d526d..a97897edd964 100644 --- a/lib/kunit/Kconfig +++ b/lib/kunit/Kconfig @@ -81,4 +81,16 @@ config KUNIT_DEFAULT_ENABLED In most cases this should be left as Y. Only if additional opt-in behavior is needed should this be set to N. +config KUNIT_AUTORUN_ENABLED + bool "Default value of kunit.autorun" + default y + help + Sets the default value of kunit.autorun. If set to N then KUnit + tests will not run after initialization unless kunit.autorun=1 is + passed to the kernel command line. The test can still be run manually + via debugfs interface. + + In most cases this should be left as Y. Only if additional opt-in + behavior is needed should this be set to N. + endif # KUNIT diff --git a/lib/kunit/debugfs.c b/lib/kunit/debugfs.c index d548750a325a..9df064f40d98 100644 --- a/lib/kunit/debugfs.c +++ b/lib/kunit/debugfs.c @@ -145,7 +145,7 @@ static ssize_t debugfs_run(struct file *file, struct inode *f_inode = file->f_inode; struct kunit_suite *suite = (struct kunit_suite *) f_inode->i_private; - __kunit_test_suites_init(&suite, 1); + __kunit_test_suites_init(&suite, 1, true); return count; } diff --git a/lib/kunit/executor.c b/lib/kunit/executor.c index 34b7b6833df3..3f39955cb0f1 100644 --- a/lib/kunit/executor.c +++ b/lib/kunit/executor.c @@ -29,6 +29,22 @@ const char *kunit_action(void) return action_param; } +/* + * Run KUnit tests after initialization + */ +#ifdef CONFIG_KUNIT_AUTORUN_ENABLED +static bool autorun_param = true; +#else +static bool autorun_param; +#endif +module_param_named(autorun, autorun_param, bool, 0); +MODULE_PARM_DESC(autorun, "Run KUnit tests after initialization"); + +bool kunit_autorun(void) +{ + return autorun_param; +} + static char *filter_glob_param; static char *filter_param; static char *filter_action_param; @@ -260,13 +276,14 @@ kunit_filter_suites(const struct kunit_suite_set *suite_set, void kunit_exec_run_tests(struct kunit_suite_set *suite_set, bool builtin) { size_t num_suites = suite_set->end - suite_set->start; + bool autorun = kunit_autorun(); - if (builtin || num_suites) { + if (autorun && (builtin || num_suites)) { pr_info("KTAP version 1\n"); pr_info("1..%zu\n", num_suites); } - __kunit_test_suites_init(suite_set->start, num_suites); + __kunit_test_suites_init(suite_set->start, num_suites, autorun); } void kunit_exec_list_tests(struct kunit_suite_set *suite_set, bool include_attr) diff --git a/lib/kunit/test.c b/lib/kunit/test.c index 089c832e3cdb..146d1b48a096 100644 --- a/lib/kunit/test.c +++ b/lib/kunit/test.c @@ -708,7 +708,8 @@ bool kunit_enabled(void) return enable_param; } -int __kunit_test_suites_init(struct kunit_suite * const * const suites, int num_suites) +int __kunit_test_suites_init(struct kunit_suite * const * const suites, int num_suites, + bool run_tests) { unsigned int i; @@ -731,7 +732,8 @@ int __kunit_test_suites_init(struct kunit_suite * const * const suites, int num_ for (i = 0; i < num_suites; i++) { kunit_init_suite(suites[i]); - kunit_run_tests(suites[i]); + if (run_tests) + kunit_run_tests(suites[i]); } static_branch_dec(&kunit_running);

9 months

3
2
0 0

[PATCH for-next v2] selftests/Makefile: override the srctree for out-of-tree builds

by Li Zhijian

Fixes an issue where out-of-tree kselftest builds fail when building the BPF and bpftools components. The failure occurs because the top-level Makefile passes a relative srctree path to its sub-Makefiles, which leads to errors in locating necessary files. For example, the following error is encountered: ``` $ make V=1 O=$build/ TARGETS=hid kselftest-all ... make -C ../tools/testing/selftests all make[4]: Entering directory '/path/to/linux/tools/testing/selftests/hid' make -C /path/to/linux/tools/testing/selftests/../../../tools/lib/bpf OUTPUT=/path/to/linux/O/kselftest/hid/tools/build/libbpf/ \ EXTRA_CFLAGS='-g -O0' \ DESTDIR=/path/to/linux/O/kselftest/hid/tools prefix= all install_headers make[5]: Entering directory '/path/to/linux/tools/lib/bpf' ... make[5]: Entering directory '/path/to/linux/tools/bpf/bpftool' Makefile:127: ../tools/build/Makefile.feature: No such file or directory make[5]: *** No rule to make target '../tools/build/Makefile.feature'. Stop. ``` To resolve this, override the srctree in the kselftests's top Makefile when performing an out-of-tree build. This ensures that all sub-Makefiles have the correct path to the source tree, preventing directory resolution errors. Signed-off-by: Li Zhijian <lizhijian(a)fujitsu.com> --- Cc: Masahiro Yamada <masahiroy(a)kernel.org> V2: - handle srctree in selftests itself rather than the linux' top Makefile # Masahiro Yamada <masahiroy(a)kernel.org> V1: https://lore.kernel.org/lkml/20241217031052.69744-1-lizhijian@fujitsu.com/ --- tools/testing/selftests/Makefile | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile index 3d8a80abd4f0..ab82278353cf 100644 --- a/tools/testing/selftests/Makefile +++ b/tools/testing/selftests/Makefile @@ -154,15 +154,19 @@ override LDFLAGS = override MAKEFLAGS = endif +top_srcdir ?= ../../.. + # Append kselftest to KBUILD_OUTPUT and O to avoid cluttering # KBUILD_OUTPUT with selftest objects and headers installed # by selftests Makefile or lib.mk. +# Override the `srctree` variable to ensure it is correctly resolved in +# sub-Makefiles, such as those within `bpf`, when managing targets like +# `net` and `hid`. ifdef building_out_of_srctree override LDFLAGS = +override srctree := $(top_srcdir) endif -top_srcdir ?= ../../.. - ifeq ("$(origin O)", "command line") KBUILD_OUTPUT := $(O) endif -- 2.44.0

9 months

4
3
0 0

[RFC PATCH v1 0/2] Add file seal to prevent future exec mappings

by Isaac J. Manjarres

Android uses the ashmem driver [1] for creating shared memory regions between processes. The ashmem driver exposes an ioctl command for processes to restrict the permissions an ashmem buffer can be mapped with. Buffers are created with the ability to be mapped as readable, writable, and executable. Processes remove the ability to map some ashmem buffers as executable to ensure that those buffers cannot be exploited to run unintended code. Other buffers retain their ability to be mapped as executable, as these buffers can be used for just-in-time (JIT) compilation. So there is a need to be able to remove the ability to map a buffer as executable on a per-buffer basis. Android is currently trying to migrate towards replacing its ashmem driver usage with memfd. Part of the transition involved introducing a library that serves to abstract away how shared memory regions are allocated (i.e. ashmem vs memfd). This allows clients to use a single interface for restricting how a buffer can be mapped without having to worry about how it is handled for ashmem (through the ioctl command mentioned earlier) or memfd (through file seals). While memfd has support for preventing buffers from being mapped as writable beyond a certain point in time (thanks to F_SEAL_FUTURE_WRITE), it does not have a similar interface to prevent buffers from being mapped as executable beyond a certain point. However, that could be implemented as a file seal (F_SEAL_FUTURE_EXEC) which works similarly to F_SEAL_FUTURE_WRITE. F_SEAL_FUTURE_WRITE was chosen as a template for how this new seal should behave, instead of F_SEAL_WRITE, for the following reasons: 1. Having the new seal behave like F_SEAL_FUTURE_WRITE matches the behavior that was present with ashmem. This aids in seamlessly transitioning clients away from ashmem to memfd. 2. Making the new seal behave like F_SEAL_WRITE would mean that no mappings that could become executable in the future (i.e. via mprotect()) can exist when the seal is applied. However, there are known cases (e.g. CursorWindow [2]) where restrictions are applied on how a buffer can be mapped after a mapping has already been made. That mapping may have VM_MAYEXEC set, which would not allow the seal to be applied successfully. Therefore, the F_SEAL_FUTURE_EXEC seal was designed to have the same semantics as F_SEAL_FUTURE_WRITE. Note: this series depends on Lorenzo's work [3] which allows for a memfd's file seals to be read in do_mmap(). [1] https://cs.android.com/android/kernel/superproject/+/common-android-mainlin… [2] https://developer.android.com/reference/android/database/CursorWindow [3] https://lore.kernel.org/all/cover.1732804776.git.lorenzo.stoakes@oracle.com/ Isaac J. Manjarres (2): mm/memfd: Add support for F_SEAL_FUTURE_EXEC to memfd selftests/memfd: Add tests for F_SEAL_FUTURE_EXEC include/linux/mm.h | 5 ++ include/uapi/linux/fcntl.h | 1 + mm/memfd.c | 1 + mm/mmap.c | 11 +++ tools/testing/selftests/memfd/memfd_test.c | 79 ++++++++++++++++++++++ 5 files changed, 97 insertions(+) -- 2.47.0.338.g60cca15819-goog

9 months

7
19
0 0

[PATCH v4 0/2] riscv/ptrace: add new regset to access original a0 register

by Celeste Liu

The orig_a0 is missing in struct user_regs_struct of riscv, and there is no way to add it without breaking UAPI. (See Link tag below) Like NT_ARM_SYSTEM_CALL do, we add a new regset name NT_RISCV_ORIG_A0 to access original a0 register from userspace via ptrace API. Link: https://lore.kernel.org/all/59505464-c84a-403d-972f-d4b2055eeaac@gmail.com/ Signed-off-by: Celeste Liu <uwu(a)coelacanthus.name> --- Changes in v4: - Fix a copy paste error in selftest. (Forget to commit...) - Link to v3: https://lore.kernel.org/r/20241226-riscv-new-regset-v3-0-f5b96465826b@coela… Changes in v3: - Use return 0 directly for readability. - Fix test for modify a0. - Add Fixes: tag - Remove useless Cc: stable. - Selftest will check both a0 and orig_a0, but depends on the correctness of PTRACE_GET_SYSCALL_INFO. - Link to v2: https://lore.kernel.org/r/20241203-riscv-new-regset-v2-0-d37da8c0cba6@coela… Changes in v2: - Fix integer width. - Add selftest. - Link to v1: https://lore.kernel.org/r/20241201-riscv-new-regset-v1-1-c83c58abcc7b@coela… --- Celeste Liu (2): riscv/ptrace: add new regset to access original a0 register riscv: selftests: Add a ptrace test to verify syscall parameter modification arch/riscv/kernel/ptrace.c | 32 ++++++ include/uapi/linux/elf.h | 1 + tools/testing/selftests/riscv/abi/.gitignore | 1 + tools/testing/selftests/riscv/abi/Makefile | 5 +- tools/testing/selftests/riscv/abi/ptrace.c | 151 +++++++++++++++++++++++++++ 5 files changed, 189 insertions(+), 1 deletion(-) --- base-commit: 0e287d31b62bb53ad81d5e59778384a40f8b6f56 change-id: 20241201-riscv-new-regset-d529b952ad0d Best regards, -- Celeste Liu <uwu(a)coelacanthus.name>

9 months

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[PATCH] selftests/rseq: Fix rseq for cases without glibc support

by Raghavendra Rao Ananta

Currently the rseq constructor, rseq_init(), assumes that glibc always has the support for rseq symbols (__rseq_size for instance). However, glibc supports rseq from version 2.35 onwards. As a result, for the systems that run glibc less than 2.35, the global rseq_size remains initialized to -1U. When a thread then tries to register for rseq, get_rseq_min_alloc_size() would end up returning -1U, which is incorrect. Hence, initialize rseq_size for the cases where glibc doesn't have the support for rseq symbols. Cc: stable(a)vger.kernel.org Fixes: 73a4f5a704a2 ("selftests/rseq: Fix mm_cid test failure") Signed-off-by: Raghavendra Rao Ananta <rananta(a)google.com> --- tools/testing/selftests/rseq/rseq.c | 19 +++++++++++++------ 1 file changed, 13 insertions(+), 6 deletions(-) diff --git a/tools/testing/selftests/rseq/rseq.c b/tools/testing/selftests/rseq/rseq.c index 5b9772cdf265..9eb5356f25fa 100644 --- a/tools/testing/selftests/rseq/rseq.c +++ b/tools/testing/selftests/rseq/rseq.c @@ -142,6 +142,16 @@ unsigned int get_rseq_kernel_feature_size(void) return ORIG_RSEQ_FEATURE_SIZE; } +static void set_default_rseq_size(void) +{ + unsigned int rseq_kernel_feature_size = get_rseq_kernel_feature_size(); + + if (rseq_kernel_feature_size < ORIG_RSEQ_ALLOC_SIZE) + rseq_size = rseq_kernel_feature_size; + else + rseq_size = ORIG_RSEQ_ALLOC_SIZE; +} + int rseq_register_current_thread(void) { int rc; @@ -219,12 +229,7 @@ void rseq_init(void) fallthrough; case ORIG_RSEQ_ALLOC_SIZE: { - unsigned int rseq_kernel_feature_size = get_rseq_kernel_feature_size(); - - if (rseq_kernel_feature_size < ORIG_RSEQ_ALLOC_SIZE) - rseq_size = rseq_kernel_feature_size; - else - rseq_size = ORIG_RSEQ_ALLOC_SIZE; + set_default_rseq_size(); break; } default: @@ -239,8 +244,10 @@ void rseq_init(void) rseq_size = 0; return; } + rseq_offset = (void *)&__rseq_abi - rseq_thread_pointer(); rseq_flags = 0; + set_default_rseq_size(); } static __attribute__((destructor)) base-commit: 40384c840ea1944d7c5a392e8975ed088ecf0b37 -- 2.47.0.338.g60cca15819-goog

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Linux-kselftest-mirror December 2024